video-based motion analysis for classroom &...
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Video-Based Motion Analysis for Classroom & Homework
Marina Milner-Bolotin
Department Curriculum and Pedagogy
The University of British Columbia
Vancouver, Canada
Catalyst 2011, October 21-22, 2011
British Columbia Science Teachers’ Association
BC ASSOCIATION OF PHYSICS TEACHERS
UBC 2011 Faculty of Education
Math & Science Fair
• Saturday, November 5
• UBC Scarfe Building
• A fun science and math day for children and their
parents
• Hands-on Science activities presented by UBC
science and math educators and prospective
teachers
• http://blogs.ubc.ca/mmilner/math-science-fair-
2011/
• FREE but RSVP is required
Let Us Warm Up…
Consider a hot air balloon travelling upwards at a constant speed of 4 m/s. A passenger
drops a small sandbag over the side of the
balloon. Produce the y(t), v(t) & a(t) stacked graphs for the sandbag after it has been
released. Assume the positive y axis is directed
upward and y=0 at the ground.
Stacked Graphs:
t, s
t, s
t, s
x, m
v, m/s
a, m/s2
How do you think
high school physics
students solve this
problem? Where do
they encounter
difficulties? What are
the causes of these
difficulties?
What is Video-Based Motion Analysis?
• Video Analysis (VA) allows to extract physical data
from digitally recorded images
• Originally used for kinematics
• Any phenomenon where visible changes in the
setup or in the device reading takes place can be
studied using VA
Video Analysis • Recording: Experiments or real-life events (i.e. roller-
coaster rides, car races, falling objects) are video
recorded, and uploaded on a computer.
• Analysis: Software (Logger Pro, Tracker, etc.) is used for
motion analysis:
o Time & position data are obtained from each frame
o Then the data are analyzed using the software
Video Analysis Software
Vernier Logger Pro: Tracker – video analysis tool
www.vernier.com http://www.cabrillo.edu/~dbrown/tracker/
Equipment
• A camcorder or a webcam connected directly to
the computer (to capture real-time event)
• Most modern digital cameras (including cell phone)
allow recording of short video clips for later analysis
Advantages of Using VA
• Easy to learn: for both students and teachers
• Cost-effective alternative to live experiments
• Excellent for fast motion that is too fast for a naked eye
• Excellent to analyze events occurring outside of the classroom
• Has enormous potential to engage students
• Data for modeling that comes from real experiments (see Tracker resources)
Example 1: Free Fall
Example 2: Ramp (x - horizontal)
Example 3: Ramp (x - along the incline)
Example 4: A Curved-Track Demo
Question: Two
metal balls are
released from
the top point
simultaneously.
Which one will
finish first?
Example 5: Unsolicited Videos
from Students
FREE Physics Movie Collection for Physics
Teaching
LivePhoto Project Example
Excellent movies to
use for Video
Analysis in your
physics class
http://livephoto.rit.e
du/LPVideos/loop/
Special Thanks!
• Prof. Tetyana Antimirova, Ryerson University, Toronto Canada
• American Association of Physics Teachers’ Colleagues who introduced me to Logger Pro and its amazing possibilities
• Vernier Technology – for excellent workshops and support
• Bob Teese, David Sokoloff, Ron Thornton, Maxine Willis and Priscilla Laws, for Video Analysis workshops
• BCAPT colleagues for their expertise and encouragement.
Resources: • Vernier-Technology. (2011). Logger Pro (Version
3.8). Portland, Oregon: Vernier Technology.
• Brown, D. (2011, August 2011). Tracker: Open Source Physics Java Video Analysis. http://www.cabrillo.edu/~dbrown/tracker/
• Teese, R. (2009, March 2009). LivePhoto Physics Project http://livephoto.rit.edu/. http://livephoto.rit.edu/wiki/
• Cooney, P. J. (2009). Making Movies for Video-Based Motion Analysis. Retrieved March 25, 2009, from http://muweb.millersville.edu/~pjcooney/making-movies/